The present invention is novel compounds that are analogs of nipecotic acid. The present invention analogs are useful for analgesic, antipsychotic, anticonvulsant, antispastic, anxiolytic activity and antisymptomatic in Huntington's disease and Parkinsonism. Specifically, the anticonvulsant activity provides usefulness as broad spectrum antiepileptic agents.
Thus, the instant invention is also novel pharmaceutical compositions and methods of use for the novel compounds disclosed herein.
With regard to the anticonvulsant or antiepileptic utility, it is despite optimal use of the several antiepileptic drugs marketed in the United States that many patients with epilepsy fail to experience seizure control and others do so only at the expense of significant toxic side effects. In the early 1970's, no convincing evidence had been published that the primary antiepileptic drugs marketed in the US at that time controlled the seizures of more than 50% or improved more than 75% of the patients with epilepsy. The availability and use of several additional drugs since that time has brought improved seizure control to many patients. Notwithstanding the beneficial effects of the current drugs, there is still a need for new antiepileptic drugs with more selective anticonvulsant effect and less toxicity. R. L. Krall, et al, Epilepsia, 19:409 (1978).
N-(4,4-diphenyl-3-butenyl) nipecotic acid as well as nipecotic acid itself are among the known compounds compared for anticonvulsant effects by W. S. Schwark and W. Loscher in "Comparison of the Anticonvulsant Effects of Two Novel GABA Uptake Inhibitors and Diazepam in Amygdaloid Kindled Rats," Naunyn Schmiedeberg's Arch. Pharmacol., 329:367-71 (1985).
In addition to Schwark and Loscher cited above, EP application 0066456 discloses that N-substituted azaheterocyclic carboxylic acids and their esters; i.e., 1-(diphenylalkyl)-3-piperidine carboxylic acid derivatives discussed above, inhibit neuronal and/or glial gamma-amino-butyric acid (GABA) uptake. The utility specifically disclosed for the compounds of EP 0066456 is for the treatment of anxiety, epilepsy, muscular and movement disorders, and mental and emotional disorders, as well as for analgesic and sedative effects.
The present invention compounds essentially differ from the compounds disclosed in EP application 0066456 by the moiety between a piperidine and aryl substituent. Thus, the present compounds are in no way taught therein.